The conventional field-effect transistor (FET) has the gate pad and the source pad fabricated thereon. The gate pad is electrically connected with the source pad by metal leads. And the source pad is electrically connected with the pins of the transistor by a plurality of metal leads. However, the structure has complicated processes and is easy to waste time while processing. In packaging, the metal leads may be broken or peeled easily to result in bad electrical connection. And further the failure rate will increase because heat dissipation is not easy after packaging.
Please refer to FIGS. 1 and 2, in order to solve the problems, a structure is developed. That is, one end of a sheet metal clip 5 is covered on the source pad 1 and the other end of the sheet metal clip 5 is electrically connected with the pins to replace the connection of the metal leads. The structure has the effects of stable electrical connection, easy to be packaged, low resistance, and better heat dissipation. However, a gate bus 2 may be cut at the source pad 1 for electrically connecting with the gate pad. The surface of the source 1 must be coated a silver paste 4 first and then the metal clip 5 is covered on the source pad 1 and pressed to fix before the metal dip 5 is fixed on the source pad 1 to electrically connect with each other. But the silver paste 4 may be overflowed and permeated in to the gate bus 2 due to pressing. As a result, the gate pad 3 is electrically connected with the source 1 all the time to result in shorting.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve this problem.